Under the chairmanship of Homer S. Ferguson of Michigan (1948) and Clyde R. Hoey of North Carolina (1949-1952), the Investigations Subcommittee of the Committee on Expenditures in Executive Departments held hearings on such matters as export control violations, for which Soviet spy William Remington was called in to testify; the trial of Nazi war criminalIlse Koch; and the MississippiDemocratic Party's sale of postal jobs, which Mississippians from rural areas attested to purchasing. A much larger scandal erupted with the "5 percenters", so-called because these men, including Presidential aide Harry H. Vaughan, were accused of charging a 5% commission for their influence in securing government contracts. A legislative reform as a result of the hearings was a restriction of one year after leaving government employment before an attorney could practice law again before the government.

As news of war crimes during the Korean War unfolded, the Subcommittee on Korean War Atrocities was headed by Charles E. Potter, and began an investigation of the abuse and murder of prisoners of war such as forced marches, maltreatments, and the shooting and murdering of prisoners shortly after capture.[1]

In 1973, Senator Henry M. Jackson, a Democrat from Washington, replaced McClellan as the Subcommittee's chairman and Senator Charles H. Percy, an Illinois Republican, became the Ranking Minority Member. During Senator Jackson's chairmanship, the Subcommittee conducted landmark hearings into energy shortages and the operation of the petroleum industry.

In January 1997 Republican Senator Susan Collins of Maine became the first woman to chair the Permanent Subcommittee on Investigations. Her Chairmanship was also notable in that she held the Senate seat of former Maine Senator Margaret Chase Smith, an opponent of Senator McCarthy. Senator John Glenn of Ohio became Ranking Member. Upon Senator Glenn's retirement from the Senate, Senator Carl Levin became Ranking Member in 1999. In June 2001, when the Democrats resumed control of the Senate, Senator Levin assumed the chairmanship of the Subcommittee until January 2003 when Senator Norm Coleman assumed the Chairmanship. When the Democrats took control of the Senate in January 2007, the chairmanship reverted to Senator Levin.

On April 13, 2011 the Committee released its report on Wall Street and the Financial Crisis: Anatomy of a Financial Collapse. The 635-page bipartisan report was issued under the chairmanship of Carl Levin and Tom Coburn and also thus referred as the Levin-Coburn Report.[4] It represents an in-depth investigation as well as a permanent record of the financial crisis of 2007–08 and took over two years of research and investigations to compile. It found "that the crisis was not a natural disaster, but the result of high risk, complex financial products; undisclosed conflicts of interest; and the failure of regulators, the credit rating agencies, and the
market itself to rein in the excesses of Wall Street."
[5]

^Potter, Charles E. (December 3, 1953). "Korean War Atrocities"(PDF, online). United States Senate Subcommittee on Korean War Atrocities of the Permanent Subcommittee on Investigations of the Committee on Government Operations. US GPO. Retrieved 2008-01-18. We marched 2 days. The first night we got some hay and we slept in the hay cuddling together to keep warm. The second night we slept in pigpens, about 6 inches space between the logs. That night I froze my feet. Starting out again the next morning after bypassing the convoy I picked up two rubber boots, what we call snow packs. They was both for the left foot. I put those on. After starting out the second morning, I didn't have time to massage my feet to get them thawed out. I got marching the next 16 days after that. During that march all the meat had worn off my feet, all the skin had dropped off, nothing but the bones showing. After arriving in Kanggye they put us up there in mud huts, Korean mud huts. We stayed there-all sick and wounded most of us was-stayed there in -the first part of January 1951. Then the Chinese come around in the night about 12 o'clock and told us those who was sick and wounded they was going to move us out to the hospital, which we knew better. There could have been such a thing but we didn't think so. --Sgt. Wendell Treffery, RA-115660.